#include <stdio.h>

void average(int a ,int b)
{
	return (a+b)/2;
	
}

int main()
{
	int a = 0;
	int b = 0;
	scanf("%d %d",&a,&b);
	
     int c = average( a, b);
	
	printf("%d",c);
	
	return 0;
 } 
